As a result of technological advances in the high density integration of solid state circuits and the economical production of sophisticated microprocessors, microcircuits are being employed in an increasing variety of applications. Electronic circuitry is being added to consumer goods to perform functions not previously available and to complement or improve existing functions. Many of the new applications involve hostile environments where mechanical shock and vibration, wide temperatures ranges, foreign matter and other potential environmental detriments to reliable circuit operation and adjustment may be encountered.
An example of a harsh environment in which microcircuits may be applied include applications to sporting goods. A particular example is the use of electronic signal evaluation, decision-making and release command circuitry in a safety ski binding. Such an electronic safety ski binding is described in U.S. Pat. No. 4,291,894 of which I am a patentee. The electronic safety ski binding described there includes a mechanical portion which in its locked condition firmly grasps a skier's boot and in its released condition permits the ski boot to separate from the binding. During skiing, the released condition is ideally achieved when forces created by skiing threaten the safety or well-being of the skier. The function of the mechanical portion of the safety ski binding is complemented, as described in the patent, by electronic circuitry which senses the skiing forces, continuously evaluates them to determine if the skier is endangered and commands the mechanical portion of the binding to release, i.e. to switch from its locked to released condition, when a situation dangerous to the skier is encountered. As disclosed in the patent, it is desirable to adjust the electronic circuitry to make a decision as to the existence or absence of a potential for injury, taking into account the skill of the skier using the binding and/or other conditions, col. 9, 11. 3-17 and col. 16, 11, 15-31.
In my U.S. Pat. No. 4,309,760, other electronic systems suitable for processing electrical signals related to skiing forces are disclosed. One embodiment of the circuitry described there includes an ability to adjust an electrical threshold which affects the force at which a binding release takes place. For examples, see col. 5, 1. 54 to col. 7, 1. 13 and col. 10, 11. 28-51.
Ski bindings, and any electronic circuitry associated with them, are subjected to wide temperature swings from storage at room temperature and above to temperatures well below freezing on the slopes. Turns, jumps and acrobatics on skis jar and vibrate the bindings and associated circuitry. Sprays of snow, water, ice, salt, and other foreign matter foul and obscure mechanical parts, penetrate seals and closures of compartments containing electronic circuitry threatening adjustable electro-mechanical components of the circuitry.
Accordingly, it is desired to provide a high degree of environmental isolation from these hostile influences for electronic circuitry adapted for use with or in sporting goods, and particularly in ski bindings. The environmental isolation must be achieved without sacrificing the ability to tune or adjust the circuitry so that different desired responses can be obtained from the same circuitry when used by different persons or used under different conditions.